Herbicidal trifluoromethyl pyridinyloxyphenoxy and pyridinylthiophenoxy propanols and derivatives thereof

ABSTRACT

2-((4-pyridinyl-2-oxy)phenoxy)propanoic acids, amides, salts and esters thereof, and nitriles derived therefrom and 2-((4-pyridinyl-2-oxy)phenoxy) propanols and esters and ethers thereof, and the corresponding 2-((4-pyridinyl-2-thio)phenoxy) propanoate and propanol compounds, all having trifluoromethyl substitution in at least one of the 3- and the 5-position in the pyridine ring with or without additional substitution at the converse position in the pyridine ring according to the following formula, are useful as herbicidal agents: ##STR1## wherein the various substituents are defined hereinbelow.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation of application Ser. No. 409,791 filed Aug. 20,1982, now abandoned, which is a divisional of application Ser. No.918,550, filed June 23, 1978, which is a continuation-in-part ofapplication Ser. No. 817,943, filed July 22, 1977, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates (a) to novel pyridinyloxyphenoxy propanoic acids,salts and esters thereof and pyridinyloxyphenoxy propanols and estersand ethers thereof, and propionitriles, and the corresponding2-((4-pyridinyl-2-thio)phenoxy)propanoate and propanol compounds, (b) toherbicidal compositions of such novel compounds and (c) to preemergentand postemergent methods of using such compounds for the control ofgrassy weeds in non-crop areas as well as in the presence of somespecified valuable crops

2. Description of the Prior Art

Belgian Pat. No. 834,495, issued Feb. 2, 1976, as well as the publishedGerman patent application equivalent thereto, viz., No. 2,546,251,published Mar. 29, 1976, describe 2-((4-pyridinyl-2-oxy)phenoxy)alkanoicacids, salts and esters having halo substitution in the 3 and/or 5 ringpositions in the pyridine ring. Published Japanese patent applicationNo. 129313/75, filed in Japan Oct. 29, 1975 teachespyridyloxyphenoxypropanols and esters thereof, while published Japanesepatent application No. 064,160/75, filed May 30, 1975, teachespyridyloxyphenoxypropionitrile compounds. The patent disclosures do notteach or suggest, however, trifluoromethyl substitution at any positionin the pyridine ring of such compounds. These prior art compounds aredisclosed to be active herbicides useful in the control of grassy weeds.

SUMMARY OF THE INVENTION

The present invention is directed to novel pyridinyloxyphenoxy propanoicacids, salts and esters having trifluoromethyl substitution in thepyridine ring according to the following formula: ##STR2## wherein: T isoxygen or sulfur;

X is Cl, Br or CF₃ ;

Y is H, Cl, Br or CF₃, provided at least one of X and Y is CF₃ ;

Z is ##STR3## or ##STR4## R₁ is H, C₁ -C₈ alkyl, benzyl, chlorobenzyl orC₃ -C₆ alkoxyalkyl;

R₄ is C₁ -C₄ alkyl;

R₅ is H or C₁ -C₄ alkyl;

R₆ is C₁ -C₇ alkyl;

M is --NHR₂ R₃ R₇, Na, K, Mg or Ca;

R₂ and R₃ are each independently selected from R₇ or --OCH₃, providedboth R₂ and R₃ cannot be simultaneously --OCH₃ and neither is --OCH₃ in--NHR₂ R₃ R₇ ; and

R₇ is H, C₁ -C₄ alkyl or C₂ -C₃ hydroxyalkyl.

The compounds of the above formula, hereinafter referred to forconvenience as "active ingredients", have been found to be especiallyactive as herbicides for the control of undesired vegetation, forexample, grassy or graminaceous weeds. Accordingly, the presentinvention also encompasses compositions containing one or more activeingredients as well as preemergent and postemergent methods ofcontrolling undesired plant growth, especially in the presence ofvaluable crops. Such methods comprise applying a herbicidally-effectiveamount of one or more active ingredients to the locus of the undesiredplants, that is, the seeds, foliage, rhizomes, stems and roots or otherparts of the growing plants or soil in which the plants are growing ormay be found.

DETAILED DESCRIPTION OF THE INVENTION

The term "herbicide" is used herein to mean an active ingredient whichcontrols or adversely modifies the growth of plants because ofphytotoxic or other effects substantial enough to seriously retard thegrowth of the plant or further to damage the plant sufficiently to killthe plant.

By "growth controlling" or "herbicidally-effective" amount is meant anamount of active ingredient which causes a modifying effect and includesdeviations from natural development, killing, regulation, desiccation,retardation, and the like.

The term "plants" is meant to include germinant seeds, emergingseedlings, rhizomes and established vegetation.

The terms "C₁ -C₄ alkyl" or "C₁ -C₇ alkyl", e.g., refer to differentsize alkyl groups which may be straight or branched.

The term "C₃ -C₆ alkoxyalkyl", for example, is meant to refer to analkoxyalkyl group having three to six carbon atoms, the alkyl portionbeing straight or branched.

The active ingredients of the present invention are generally oils orcrystalline solids at ambient temperatures which are soluble in manyorganic solvents commonly employed as herbicidal carriers. The activeingredients of the above formula wherein T is oxygen, X is CF₃, Y is Clor H, and Z is ##STR5## wherein R₁ is C₁ -C₈ alkyl constitute preferredembodiments of the present invention. The active ingredients of theabove formula wherein T is oxygen, X is CF₃, Y is Cl, Br, CF₃ orhydrogen, Z is ##STR6## wherein R₂ and R₃ are each independentlyhydrogen--OCH₃, or C₁ -C₄ alkyl constitute additional preferredembodiments. Yet additional preferred embodiments are the presentcompounds wherein T is sulfur, X is CF₃, Y is Cl, and Z is ##STR7##wherein R₁ is H or C₁ -C₈ alkyl.

The active ingredients, i.e., new compounds, of the present inventionwherein T is oxygen are readily prepared by the reaction of4-hydroxyphenoxy-2-propanoic acid or an ester thereof with a substitutedpyridine having the requisite substitution in the 3- and/or 5-ringpositions in addition to 2-halo substitution. The pyridine compound usedas starting material is itself prepared from a 2-halopyridine compound,generally the 2-chloro substituted compound, having trichloromethylsubstitution in either or both of the 3- and 5-ring positions inaddition to any desired chloro or bromo substitution at the 3- or5-positions, if not occupied by a CCl₃ group, by reacting the pyridinecompound with a fluorinating material such as antimony trifluoridewhereupon the trichloromethyl group or groups are converted totrifluoromethyl groups, as well understood in the art.

The new compounds of the present invention wherein T is sulfur aresimilarly prepared by the reaction of 4-mercaptophenoxy-2-propanoic acidor an ester thereof with an appropriate substituted pyridine insubstantially the same manner as described above.

The reaction between such a substituted pyridine and the said hydroxy-or mercapto-phenoxy propanoic acid is rather readily carried out in apolar solvent such as dimethyl sulfoxide to which has been added a smallamount of aqueous or powdered sodium hydroxide. Reaction is usuallycarried out at a temperature in the range of about 70° to about 125° C.over a period of about 1 to 3 hours under ambient atmospheric pressure.The reaction mixture is then allowed to cool and is poured into aquantity of cold water and acidified with hydrochloric acid, whereuponthe product precipitates and is separated and purified as may berequired.

The propanoate esters of the present invention may be prepared insubstantially the same manner as set forth above for the propanoicacids, using the requisite ester of 4-hydroxyphenoxy-2-propanoic acid or4-mercaptophenoxy-2-propanoic acid to react with the appropriatelysubstituted 2-halopyridine. Or, if desired, the appropriate propanoicacid of the invention is esterified by first converting to the acidchloride with thionyl chloride and then reacting the acid chloride withthe appropriate alcohol, or, mercaptan, such as, ethyl mercaptan, propylmercaptan or butyl mercaptan, according to generally accepted proceduresor the classic method of reacting an alcohol and an acid in the presenceof a little sulfuric acid may be followed.

The propanoic acid compounds of the invention after conversion to theacid chloride may also be reacted with (a) ammonia to form the simpleamide, (b) with an alkyl amine to form an N-alkyl amide or N,N-dialkylamide, or (c) with a methoxy amine to form an alkoxy amide.

The simple amide serves as preferred starting material for themanufacture of the present nitriles, which are obtained upon reaction ofthe amide with phosphorous oxychloride.

The propanoate metal salts of the invention are prepared from thepropanoic acid form of the compound by simply reacting the carboxylicacid with the requisite inorganic base, such as NaOH, KOH, Ca(OH)₂ orMg(OH)₂. The amine salts are prepared by reacting the propanoic acidcompound with the requisite amine, for example, triethanolamine ortrimethylamine.

The compounds according to the invention which are substituted propanolsare prepared preferably from one of the above described esters of thepropanoic acid form of the compound, such as the methyl ester, byreaction of the ester with sodium borohydride in a polar solvent mediumsuch as methanol, reaction being carried out initially at a temperaturebelow about 30° C. during an initial period of 1 to 2 hours after whichthe temperature is brought to about 50° to 60° C. and the solvent thenstripped off. The reaction product is then admixed with water andextracted with a water-immiscible organic solvent. Removal of thesolvent leaves an oily product.

Esterification of such alcohol is carried out according to methodsgenerally known in the art in which, e.g., an acid chloride is reactedwith the alcohol in solvent medium in the presence of a hydrogenchloride acceptor, such as triethylamine. The hydrochloride salt isfiltered off and the solvent stripped, leaving an oily product.

Ethers of the alcohols of the invention are prepared by reacting thealcohol with, e.g., sodium hydride in a polar solvent such as dimethylformamide at a temperature of about 35° to 60° C., after which an alkylbromide is added to the reaction mixture and heated to 75° to 100° C.for one to two hours. The solvent medium is then stripped off underreduced pressure and the crude product is poured into cold water andfinal product taken up with water immiscible solvent such as heptane.The solvent, on being stripped off, leaves an oily product.

In an alternate process for making the present propanoic acid compounds,a salt, e.g., the sodium salt, of 4-methoxyphenol, or of 4mercaptophenol, is dissolved in a solvent such as dimethyl sulfoxide andthe requisite trifluoromethyl-substituted 2-chloropyridine is added tothe solution of the methoxy phenol and reacted in the presence of alittle aqueous sodium hydroxide at a temperature in the range of about70° to 130° C. and over a time interval of about 30 to 45 minutes. Thereaction mixture is then cooled somewhat and poured over ice. The solidproduct is filtered off and washed with water and taken up in a solventmixture and reprecipitated therefrom. The methoxy group, if present, isthen cleaved off the phenyl ring by refluxing the compound in 48% byweight HBr for about an hour and after purification, precipitated fromacidic solution and recovered, as by filtration, and dried. Thetrifluoromethyl-substituted 2-pyridinyloxy phenol, ortrifluoromethyl-substituted 2-pyridinylthiophenol, is then dissolved ina solvent such as dimethyl sulfoxide, anhydrous powdered sodiumhydroxide is added thereto and reacted therewith for a few minutes atabout 75° to 85° C. Then an ester, such as the ethyl ester, of2-bromopropanoic acid is added to the reaction mixture and stirred for atime, such as about half an hour, at approximately 100° C. or up toabout 2 hours in the case of the sulfur bridged compound. The reactionmixture is then allowed to cool and poured over ice or simply into coldwater whereupon an oily layer separates which can be recovered by takingup in a water-immiscible solvent and subsequently stripping the solventoff leaving an oily product. The product so obtained will be the alkylester of the propanoic acid compound. In carrying out the severalreactions of this alternate process, the reactants are usually mixedwith a carrier medium, such as, for example, methylethyl ketone,methylisobutyl ketone or an aprotic polar solvent such asdimethylformamide, dimethylacetamide, dimethylsulfoxide,N-methylpyrrolidone, hexamethylphosphoramide or sulfolane. The firststep condensation is generally carried out at a temperature of at least50° C., preferably about 70° to about 150° C. and during a reactionperiod of about 1 to about 20 hours, preferably about 1 to about 10hours. The second condensation reaction is carried out under similarreaction conditions except that the reaction is usually accomplished ina shorter period of time such as about 0.5 to 10 hours, typically usingone of the aprotic solvents such as dimethylsulfoxide as reactionmedium. The dealkylation step, where employed, is carried out using as asuitable dealkylation agent, a hydro acid such as hydrobromic acid orhydriodic acid employed as a concentrated aqueous solution of about 40to about 60 percent by weight concentration. Reaction is carried out ata reflux temperature which usually falls in the range of about 75° toabout 150° C. but preferably is about 100° C. to 140° C. Thedealkylation reaction is generally completed in about 1 to about 10hours.

The active ingredients of the above formula wherein Z is --CH₂ OOCR₆ arereadily prepared from the requisite 2-propanoic acid compound, preparedas described above, followed by esterification with a primary alcoholconveniently available, such as methanol, and in the presence of a smallamount of sulfuric acid, after which the ester is reduced to the alcoholupon reaction with sodium borohydride in aqueous medium and at close toambient room temperature. After removal of excess primary alcohol theproduct is extracted from the reaction mixture with a water-immisciblesolvent or solvent mixture such as methylene chloride-heptane. Finally,the solvent is stripped off and removed under reduced pressure leavingthe product which is usually an oil.

The so-produced substituted propanol is esterified, if desired, byreacting it with the acid chloride of the esterifying acid in solventmedium, such as toluene, containing in admixture, an HCl acceptor suchas triethyl amine. Reaction proceeds steadily over about a 1 to 1.5 hourperiod at a temperature in the range of about 100° to about 135° C. Theprecipitated trialkylamine hydrochloride is filtered off and the solventmedium stripped off. Subsequently, the residue is preferably washed withwater and then taken up in hot heptane, dried, and the heptane distilledoff leaving an oily product.

The substituted propionitriles of the invention are prepared using thepropanoic acid compound as the starting material. The carboxylic acid isreacted with thionyl chloride to form the acid chloride which is in turnreacted with NH₄ OH to produce the amide. The amide is reacted withPOCl₃ to form the nitrile.

The following examples illustrate the present invention and the mannerby which it can be practiced but as such are not to be construed aslimitations upon the overall scope of the invention.

EXAMPLE 1

2-Chloro-5-(trichloromethyl)pyridine (23.0 grams ("g"); 0.1 mole) wasmixed with antimony trifluoride (22.3 g; 0.125 mole) and then chlorinegas (9.0 g; 0.126 mole) was passed into the stirred mixture over aperiod of 8 minutes during which time the temperature rose from ambientto 100° C. The reaction mixture was stirred for an additional 20 minutesbefore adding 25 milliliters of concentrated HCl plus 27 milliliters ofwater and steam distilling off any unreacted starting material andvolatile chlorides and fluorides. Thereafter, pentane was added to thereceiver vessel to take up the solid product which was subsequentlyrecovered by distilling off the solvent.

The crystalline product obtained had a melting temperature of 30°-1° C.and upon analysis was found to contain 39.56% carbon; 1.78% hydrogen;7.72% nitrogen; and 19.42% chlorine. The theoretical composition for2-chloro-5-(trifluoromethyl)pyridine is 39.69% carbon; 1.66% hydrogen;7.72% nitrogen; and 19.53% chlorine.

The following substituted pyridines are prepared in a similar manner:

    ______________________________________                                        Ring Substituents On Pyridine                                                 2      3        5        Physical Property                                    ______________________________________                                        Cl     CF.sub.3 CF.sub.3 (B.P.) 94-96° C. @ 109 mm Hg                  Cl     Cl       CF.sub.3 (B.P.) 50-51° C. @ 21 mm Hg                   Cl     CF.sub.3 Cl       n.sup.25°  = 1.4825                           Cl     Br       CF.sub.3                                                      ______________________________________                                    

EXAMPLE 2

2-(4-hydroxyphenoxy)propanoic acid (2.35 g; 0.0129 mole) was dissolvedin dimethylsulfoxide (16 ml) and then a solution of sodium hydroxide(1.06 g; 0.026 mole) in 3.5 ml of water was added. This mixture wasstirred and heated to about 60° C. over a 20 minute period in order toinsure formation of the disodium salt. Next a solution of2-chloro-3,5-bis(trifluoromethyl)pyridine (2.73 g; 0.0129 mole) in 8 mlof dimethylsulfoxide reaction medium was added over a 3 minute periodand the mixture then warmed to 110° C. in 35 minutes. The mixture wasthen heated at 105°-110° C. for an additional 45 minutes, allowed tocool for 30 minutes, and then poured into cold water. The resultingcrude, gummy product was taken up in hot toluene, treated with activatedcharcoal, and filtered. The toluene was then flashed off and the productwas extracted with pentane which was chilled resulting in the separationof a crystalline product having a melting temperature of 80.5°-83° C.The product was found on analysis to contain 48.87% carbon; 3.14%hydrogen; and 3.59% nitrogen. The theoretical composition for2-(4-(3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acid is48.62% carbon; 2.80% hydrogen; and 3.54% nitrogen, thus confirming theobtention of the anticipated product.

In a manner similar to the foregoing procedure, using the requisitestarting materials, the following 4-pyridinyloxyphenoxy propanoic acidcompounds of the invention are prepared:

    ______________________________________                                        Ring                                                                          Substituents                                                                           Melting                                                              On Pyridine                                                                            Temperature,                                                                             Elemental Analysis, % By Weight*                          3    5       °C. C      H     N     Cl                                 ______________________________________                                        Cl   CF.sub.3                                                                              105.5-107  49.73  3.25  3.78  9.66                                                       (49.81)                                                                              (3.06)                                                                              (3.87)                                                                              (9.80)                             CF.sub.3                                                                           CF.sub.3                                                                              80.5-83    48.87  3.14  3.59  --                                                         (48.62)                                                                              (2.80)                                                                              (3.54)                                   --   CF.sub.3                                                                                97-100   54.91  3.77  4.27  --                                                         (55.05)                                                                              (3.70)                                                                              (4.28)                                   CF.sub.3                                                                           Cl        115-118  49.79  3.21  3.99  9.77                                                       (49.81)                                                                              (3.06)                                                                              (3.87)                                                                              (9.80)                             Br   CF.sub.3                                                                 CF.sub.3                                                                           Br                                                                       ______________________________________                                         *Theoretical composition shown in parenthesis                            

EXAMPLE 3

3,5-bis(trifluoromethyl)-2-pyridinyloxy-4-phenoxypropanoic acid (16.0 g;0.0405 mol) was refluxed with 110 ml of thionyl chloride for 26 minutesand then the unreacted thionyl chloride was distilled off. The resultingacid chloride was put into 40 ml of methanol. Triethylamine (5.2 g;0.0514 mol) was put into 75 ml of methanol. The acid chloride solutionwas then added and the reaction mixture was taken to reflux and refluxedfor 30 minutes. The methanol was removed by distillation and the crudeproduct was washed with water and taken up in heptane. The heptane wasremoved and 15 grams of amber oil was obtained which had a refractiveindex of 1.4832 at 25° C.

The product had the following elemental analysis:

    ______________________________________                                                 C           H      N                                                 ______________________________________                                        Calculated 49.88         3.20   3.42                                          Found      49.97         3.20   3.52                                          ______________________________________                                    

These results confirm the obtention of methyl2-(4-((3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate.

Other active ingredients of the present invention are similarly preparedby employing procedures analogous to those set forth in the aboveexample and the foregoing teachings of the specification. Such otheractive ingredients include the following compounds:

    __________________________________________________________________________     ##STR8##                                                                                                            Elemental Analysis, % By Weight*       X  Y  R                   Refractive Index @ 25° C.                                                           C    H   N   Cl                        __________________________________________________________________________    CF.sub.3                                                                         CF.sub.3                                                                         (CH.sub.2).sub.7 CH.sub.3                                                                         1.4743       .sup. 55.65                                                                        .sup. 5.02                                                                        .sup. 2.96                                                                        --                                                               (56.80)                                                                            (5.36)                                                                            (2.76)                        Cl CF.sub.3                                                                         (CH.sub.2).sub.3 CH.sub.3                                                                         1.5076       .sup. 54.49                                                                        .sup. 4.69                                                                        .sup. 3.41                                                                        8.60                                                             (54.62)                                                                            (4.58)                                                                            (3.35)                                                                            (8.49)                    CF.sub.3                                                                         Cl (CH.sub.2).sub.3 CH.sub.3                                                                         1.5080       .sup. 54.61                                                                        .sup. 4.65                                                                        .sup. 3.34                                                                        8.47                                                             (54.62)                                                                            (4.58)                                                                            (3.35)                                                                            (8.49)                    Br CF.sub.3                                                                         C.sub.2 H.sub.5                                                         CF.sub.3                                                                         H                                                                                 ##STR9##           1.5432       .sup. 49.94 (51.07)                                                                .sup. 2.76 (2.68)                                                                 .sup. 7.25 (7.44)             CF.sub.3                                                                         Br                                                                                ##STR10##                                                              CF.sub.3                                                                         H  (CH.sub.2).sub.2 CH.sub.3                                               CF.sub.3                                                                         Cl CH.sub.2CH.sub.2OC.sub.4 H.sub.9                                        CF.sub.3                                                                         --                                                                                ##STR11##                                                              CF.sub.3                                                                         CF.sub.3                                                                         (CH.sub.2 CH.sub.2 O) .sub.5H                                           CF.sub.3                                                                         Cl                                                                                ##STR12##                                                              CF.sub.3                                                                         Cl CH.sub.2CH.sub.2OCH.sub.3                                               CF.sub.3                                                                         Cl (CH.sub.2).sub.2O(CH.sub.2).sub.3 CH.sub.3                                                        1.5061       .sup. 54.61                                                                        .sup. 5.02                                                                        .sup. 3.03                                                                        7.68                      __________________________________________________________________________     *Theoretical composition shown in parenthesis                            

In a similar manner to the foregoing Example butyl mercaptan was usedinstead of methanol and the compound obtained having a refractive indexat 25° C. of 1.5330 was2-(4-(3-chloro-5-trifluoromethyl)-2-pyridinyloxy)phenoxy propanethioicacid, -s-butyl ester.

EXAMPLE 4

To 5.0 g (0.0138 mole) of2-(4-(3-chloro-5-(trifluoromethyl)pyridinyl-2-oxy)phenoxy)propanoic acidwas added 30 ml of SOCl₂ and the mixture heated at reflux for about 20minutes after which unreacted SOCl₂ was removed on a still under wateraspirator vacuum. The resulting syrup was added to a stirred solution of30 ml (0.028 mole) of concentrated aqueous NH₄ OH in 40 ml ofacetonitrile. The mixture was stirred at a temperature of 25° C. for 15minutes and filtered, thus recovering crystals of solid product whichhad formed. The recovered crystals exhibited a melting temperature of140°-42° C. On elemental analysis, the crystals were found to contain49.50% carbon; 3.44% hydrogen; 10.01% chlorine; and 7.76% nitrogen.Theoretical composition for2-(4-(3-chloro-5-(trifluoromethyl)pyridinyl-2-oxy)phenoxy)propionamideis 49.94% carbon; 3.35% hydrogen; 9.83% chlorine; and 7.76% nitrogen.

Other 2-((4-(trifluoromethylsubstituted)-2-pyridinyl)oxy)phenoxypropionamides of the invention areprepared using procedures similar to the foregoing using the requisitestarting materials. Such active ingredients include the followingcompounds:

    __________________________________________________________________________     ##STR13##                                                                                                 Elemental Analysis, % By Weight*                 X  Y  A         Melting Temperature °C.                                                             C    H   N   Cl                                  __________________________________________________________________________    Cl CF.sub.3                                                                         NH.sub.2  151-152      48.56                                                                              3.37                                                                              7.57                                                                              9.57                                                             (49.94)                                                                            (3.35)                                                                            (7.77)                                                                            (9.83)                              CF.sub.3                                                                         Cl NHCH.sub.3                                                                              146-147      51.14                                                                              3.73                                                                              7.37                                                                              9.63                                                             (51.78)                                                                            (3.76)                                                                            (7.47)                                                                            (9.46)                              CF.sub.3                                                                         CF.sub.3                                                                         N(n-C.sub.4 H.sub.9).sub.2                                                              (n.sup.25°  = 1.4844)                                                               56.30                                                                              5.48                                                                              5.06                                                                              --                                                               (56.91)                                                                            (5.57)                                                                            (5.33)                                  CF.sub.3                                                                         -- N(CH.sub.3).sub.2                                                                       (n.sup.25°  = 1.5247                                                                57.99                                                                              5.04                                                                              7.74                                                                              --                                                               (57.6)                                                                             (4.84)                                                                            (7.9)                                   CF.sub.3                                                                         -- NH.sub.2  69-70        55.3 4.09                                                                              8.62                                                                              --                                                               (55.22)                                                                            (4.02)                                                                            (8.58)                                  CF.sub.3                                                                         CF.sub.3                                                                         NH.sub.2  150.5-152    48.78                                                                              3.17                                                                              6.96                                                                 (48.75)                                                                            (3.05)                                                                            (7.1)                                   CF.sub.3                                                                         Br NH.sub.2  --                                                            CF.sub.3                                                                         Cl NHCH.sub.3                                                                              146-147      51.19                                                                              3.73                                                                              7.37                                                                              9.63                                                             (51.28)                                                                            (3.76)                                                                            (7.47)                                                                            (9.46)                              CF.sub.3                                                                         -- NHCH.sub.3                                                              CF.sub.3                                                                         Cl NHnC.sub.4 H.sub.9                                                      Br CF.sub.3                                                                         NHnC.sub.3 H.sub.7                                                      CF.sub.3                                                                         -- NHOCH.sub.3                                                             CF.sub.3                                                                         Cl NHCH.sub.2 CH.sub.2 OH                                                                  (n.sup.25 = 1.5434)                                                                        50.71                                                                              3.81                                                                              6.41                                                                              8.96                                                             (50.44)                                                                            (3.98)                                                                            (6.92)                                                                            (8.76)                              CF.sub.3                                                                         Cl NHOCH.sub.3                                                                             135-6                                                         __________________________________________________________________________     *Theoretical composition shown in parenthesis                            

EXAMPLE 5

5-chloro-3-trifluoromethyl-2-pyridinyloxy-4-phenoxypropionamide (4.5 g;0.01248 mols) was refluxed with 20 ml of phosphorous oxychloride for atotal time of 1 hour and 45 minutes. The POCl₃ was distilled off and theremaining reaction mixture was poured over ice and extracted withheptane. On cooling a crystalline product was obtained with a meltingrange of 61.5°-62.5° C. The anticipated product was2-(4-(5-chloro-3-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propionitrile.The following elemental analysis was obtained:

    ______________________________________                                                 C     H          N       Cl                                          ______________________________________                                        Calculated 52.57%  2.94%      8.18% 10.35%                                    Found      52.48%  3.01%      8.17% 10.14%                                    ______________________________________                                    

Other active nitrile compounds of the present invention are similarlyprepared by employing the procedures analogous to those set forth in theabove example and the foregoing teaching of the specification. Suchother active ingredients include the following compounds:

    ______________________________________                                         ##STR14##                                                                    Melting                                                                       Temperature    Elemental Analysis, % By Weight*                               X    Y      °C. C      H     N      Cl                                 ______________________________________                                        CF.sub.3                                                                           Cl     49-52      52.71  3.07  10.47  7.47                                                      (52.57)                                                                              (2.94)                                                                              (10.35)                                                                              (8.17)                             CF.sub.3                                                                           --     38-40      58.16  3.79  8.81   --                                                        (58.44)                                                                              (3.57)                                                                              (9.08)                                    CF.sub.3                                                                           CF.sub.3                                                                             54-55      49.94  2.76  7.25                                                             (51.07)                                                                              (2.68)                                                                              (7.44)                                    Br   CF.sub.3                                                                             --                                                                Cl   CF.sub.3                                                                             61.5-62.5  52.48  3.01  8.17   10.14                                                     (52.57)                                                                              (2.94)                                                                              (8.18) (10.35)                            ______________________________________                                         *Theoretical composition shown in parenthesis                            

EXAMPLE 6

In each of a series of metal salt preparations 60 milligrams (mg) of oneof the propanoic acids of the invention was stirred into severalmilliliters (ml) of water and (an aqueous solution of base added theretoin the amount needed for neutralization plus a slight excess estimatedto be 10% excess upon obtaining a color change to yellow green inuniversal indicator. The propanoic acids, the molar amounts employed,the bases employed and the estimated amounts of such bases are tabulatedas follows, the propanoic acid being identified by ring substitution onthe pyridinyl ring:

    ______________________________________                                        Ring Substituents                                                                        Propanoic            mg of                                         5      3       Acid, mols.                                                                              Base    Base (estimated)                            ______________________________________                                        CF.sub.3                                                                             --      0.183      NaOH    7.34                                        CF.sub.3                                                                             Cl      0.165      KOH     9.25                                        CF.sub.3                                                                             CF.sub.3                                                                              0.152      *NH.sub.4 OH                                                                          5.32                                        ______________________________________                                         *The NH.sub.4 OH was employed in the form of concentrated ammonium            hydroxide.                                                               

The aqueous solutions so obtained are conveniently used in herbicidalapplications with or without further dilution. The salts may berecovered by evaporation of the water from the solutions and purified bycareful recrystallization, if desired.

The magnesium and calcium salts of the identified propanoic acids aswell as the other propanoic acids of the invention are prepared insubstantially the manner described above.

EXAMPLE 7

In each of a series of amine salt preparations 60 mg of one of thepropanoic acids of the invention was stirred into several ml of waterand a solution of alkyl amine or alkanolamine added thereto in theamount needed for neutralization plus an estimated 10 percent excess ofbase believed to be reached upon titrating to the yellow-green color ofuniversal indicator. The propanoic acids, here identified by ringsubstituents, the molar amount of propanoic acid, the base employed andthe estimated amounts of each base, are tabulated as follows:

    ______________________________________                                        Ring Substituents                                                                        Propanoic            mg of                                         5      3       Acid, mols.                                                                             Base     Base (estimated)                            ______________________________________                                        CF.sub.3                                                                             --      0.183     NH.sub.2 C.sub.2 H.sub.5 OH                                                            11.19                                       CF.sub.3                                                                             Cl      0.165     (C.sub.2 H.sub.5).sub.3 N                                                              16.68                                       Cl     CF.sub.3                                                                              0.165     C.sub.2 H.sub.5 NH.sub.2                                                                7.43                                       ______________________________________                                    

The aqueous solutions so obtained are conveniently used in herbicidalapplications with or without further dilution. The salts may berecovered by evaporation of water from the solutions and purified bycareful recrystallization, if desired.

The preparation of other amine salts such as the triethanolamine anddiethanolamine salts, the tripropylamine salt and the butylamine saltsare prepared in substantially the manner described above.

EXAMPLE 8

Sodium borohydride (6.35 g; 0.1716 mols) was dissolved in 25 ml of waterand added over a ten minute period to a solution of methyl2-(4-((3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propionate (11.7g; 0.02859 mols) dissolved in 155 ml of warm methanol. During theaddition the temperature was kept between 25° and 30° C. The mixture wasallowed to stir at room temperature for 40 minutes and was then allowedto warm to 42° C. over a 25 minute period. The methanol was then removedby distillation and cold water was added to the crude product which wasthen extracted with a methylene chloride-heptane mixture. The solventswere distilled off leaving an orange colored oil with an index ofrefraction of 1.5028 at 25° C. The anticipated product was2-(4-((3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanol. Theproduct had the following elemental analysis:

    ______________________________________                                                   C        H         N                                               ______________________________________                                        Calculated   50.40%     3.44%     3.67%                                       Found        51.01      3.64      3.86                                        ______________________________________                                    

Other pyridinyloxyphenoxypropanols of the present invention aresimilarly prepared by employing procedures analogous to those set forthin the above example and the foregoing teachings of the specification.Such compounds include the following:

    ______________________________________                                         ##STR15##                                                                                     Elemental Analysis,                                          Refractive       % By Weight*                                                 X    Y      Index @ 25° C.                                                                      C     H     N     Cl                                 ______________________________________                                        CF.sub.3                                                                           Cl     1.5377       51.75 3.91  4.04  10.32                                                       (51.81)                                                                             (3.77)                                                                              (4.03)                                                                              (10.2)                             CF.sub.3                                                                           --                                                                       CF.sub.3                                                                           Br                                                                       Cl   CF.sub.3                                                                 Br   CF.sub.3                                                                 ______________________________________                                         *Theoretical composition shown in parenthesis                            

EXAMPLE 92-(4-((3,5-bis(triflouromethyl)-2-pyridinyl)oxy)phenoxy)propanol (5.45g; 0.0171 mols) were taken up in 75 ml of toluene and placed in a roundbottom reaction flask and 1.8 g of triethylamine was added thereto. Thenoctoyl chloride (3.05 g; 0.01875 mols) as a solution in 18 ml of toluenewas added to the propanol over a 3 minute period at a temperature in therange of 25°-30° C. The mixture was stirred for about an hour at ambientroom temperature and then refluxed for about one hour. At the end of thereaction period, the separated hydrochloride salt was filtered off andthe toluene was stripped off on a rotary evaporator. The residue waspoured into ice water and taken up by extraction with heptane. Theheptane extracts were dried and the heptane was removed by distillation,leaving an oil with a refractive index of 1.4740 at 25° C. Theanticipated product was2-(4-((3,5-bis(triflouromethyl)-2-pyridinyl)oxy)phenoxy)propyloctanoate. The product had the following elemental analysis:

    ______________________________________                                                 C           H      N                                                 ______________________________________                                        Calculated 56.80         5.36   2.76                                          Found      58.0          5.88   2.79                                          ______________________________________                                    

Other propyl esters of the present invention are similarly prepared byemploying procedures analogous to those set forth in the above exampleand the foregoing teachings of the specification. Such other activeingredients include the following compounds:

    __________________________________________________________________________     ##STR16##                                                                                                  Elemental Analysis, % By Weight*                X  Y  B          Refractive Index @ 25° C.                                                           C   H   N   Cl                                  __________________________________________________________________________    CF.sub.3                                                                         Cl CH.sub.3   1.5230       52.26                                                                             3.99                                                                              3.69                                                                              9.38                                                              (52.38)                                                                           (3.88)                                                                            (3.59)                                                                            (9.10)                              CF.sub.3                                                                         -- (CH.sub.2).sub.6 CH.sub.3                                               CF.sub.3                                                                         Cl C.sub.2 H.sub.5                                                         CF.sub.3                                                                         Br CH.sub.3                                                                CF.sub.3                                                                         CF.sub.3                                                                         i-C.sub.3 H.sub.7                                                       Cl CF.sub.3                                                                         (CH.sub.2).sub.2OC.sub.2 H.sub.5                                        __________________________________________________________________________     *Theoretical composition shown in parenthesis                            

EXAMPLE 10

Sodium hydride (0.8 g; 0.0334 mols) is dissolved in 30 ml of drydimethyl formamide and then a solution of2-(4-((3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanol (5.5 g;0.0176 mols) in 50 ml of dry dimethylformamide is added to the sodiumhydride solution over a four minute period and then stirred for an hourat 40°-50° C. A solution of 1-bromobutane (2.4 g; 0.0175 mols) in 25 mlof dry dimethylformamide is then added over a six minute period. Thereaction mixture is then slowly heated to 90° C. over a 30 minute periodand held at 90° C. for an hour and ten minutes. The reaction mixture isthen stirred and heated at 105°-115° C. for 2 hours. Thedimethylformamide is then stripped off under partial vacuum and thecrude product poured into cold water and extracted with heptane. Theheptane is removed by distillation leaving an oil as product.

Other active ingredients of the present invention are similarly preparedby employing procedures analogous to those set forth in the aboveexample and the foregoing teachings of the specification. Such otheractive ingredients include the following compounds:

    ______________________________________                                         ##STR17##                                                                    X        Y              E                                                     ______________________________________                                        CF.sub.3 CF.sub.3       C.sub.2 H.sub.5                                       CF.sub.3 --             CH.sub.3                                              Cl       CF.sub.3       n-C.sub.4 H.sub.9                                     CF.sub.3 Br             i-C.sub.3 H.sub.7                                     CF.sub.3 Cl                                                                                            ##STR18##                                            CF.sub.3 --                                                                                            ##STR19##                                             CF.sub.3                                                                              Cl             SO.sub.3 Na                                           ______________________________________                                    

EXAMPLE 11

The following series of preparations illustrate an alternate method ofsynthesizing the propanoate esters and from such compounds the propanoicacids of the invention. A solution of the sodium salt of 4-methoxyphenol was prepared by dissolving the methoxy phenol (7.45 g; 0.06 mole)in 45 ml of dimethylsulfoxide and adding a solution of sodium hydroxide(2.4 g; 0.06 mole) in 7 ml of water. A solution of2-chloro-5-(trifluoromethyl)pyridine (9.0 g; 0.05 mole) in 40 ml ofdimethylsulfoxide was then added to the above sodium phenate solutionover an 11 minute period. During the addition, the temperature rose toabout 80° C. and then the reaction mixture was heated to 124° C. over a26 minutes interval and the temperature maintained for 15 minutes. Atthe end of this time, the reaction mixture was cooled to 75° C. andpoured over ice. The solid product was collected on a filter, washed andtaken up in a toluene-hexane mixture. This solution on cooling yielded9.7 grams of solid product having a melting temperature of 49.5°-50.5°C. and having a composition of 58.02% carbon; 3.86% hydrogen; and 5.22%nitrogen. The theoretical composition is 57.99% carbon; 3.74% hydrogen;and 5.20% nitrogen, confirming the product to be5-(trifluoromethyl)-2-(4-methoxyphenoxy)pyridine.

The 5-(trifluoromethyl)-2-(4-methoxyphenoxy)pyridine (10.95 g; 0.0407mole) was refluxed with 50 ml of 48 percent by weight aqueoushydrobromic acid solution for one hour. At the end of this time, thereaction mixture was cooled, poured over ice and the separated solidscollected on a filter. The product was purified by taking it up indilute caustic solution, extracting the solution with chloroform toremove unreacted starting material and then acidifying the solution toprecipitate free phenol. The dried crystalline phenol product had amelting temperature of 89°-91° C. and was found to contain 56.21%carbon; 3.27% hydrogen; and 5.44% nitrogen. The theoretical compositionof 4-(5-(trifluoromethyl)-2-(pyridinyl)oxy)phenol is 56.48% carbon;3.16% hydrogen; and 5.49% nitrogen.

The 4-(5-(trifluoromethyl)-2-(pyridinyl)oxy)phenol (4.95 g; 0.0194 mole)was dissolved in dimethylsulfoxide (41 ml) as reaction medium, thensodium hydroxide (0.78 g; 0.014 mole) was added as a dry powder and themixture stirred for about 10 minutes and warmed to about 80° C.Ethyl-2-bromopropionate (4.2 g; 0.0233 mole) was then added in oneportion and the mixture stirred for about 35 minutes at 96° C. Thesolution was then cooled, poured over ice and the oil which separatedtaken up in petroleum ether containing 20 percent by volume methylenechloride. The separated solvent phase was stripped of solvent leaving anoily product weighing 6.3 g. An infrared scan of a sample of the oilconfirmed the ester structure of the anticipatedethyl-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propionate.

Ethyl-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propionate (6.3g; 0.0177 mole) was dissolved in 28 ml of 2-B-ethanol and a solution ofsodium hydroxide (1.06 g; 0.0266 mole) in 28 ml of water was added. Thereaction mixture was heated to 75° C. for 5 minutes and then poured into150 ml of cold water and acidified with 4 g of concentrated hydrochloricacid. The crude acid product which precipitated was washed with hotpetroleum ether and dried. The resulting product exhibited a meltingtemperature of 97°-100° C. and was found on analysis to contain 54.91%carbon; 3.77% hydrogen; and 4.28% nitrogen. The theoretical compositionfor 2-(4-(5-trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propionic acid is55.05% carbon; 3.70% hydrogen; and 4.28% nitrogen, indicating theexpected product was obtained.

Other active ingredients of the present invention in which Z in thestructural formula set forth is ##STR20## are similarly prepared byemploying procedures analogous to those set forth in the above exampleand the foregoing teachings of the specification by reacting theappropriately substituted 2-halopyridine with 4-methoxy phenol,hydrolyzing the 4-methoxy group to a 4-hydroxy group, and condensing thepyridinyloxy phenol with an alkyl 2-bromopropanoate ester, the esterbeing then hydrolyzed if it is desired to obtain the propanoic acid formof the compound.

EXAMPLE 12

4-Mercaptophenol (7.6 gm., 0.06 moles) was dissolved in 70 ml ofdimethyl(sulfoxide and a solution of sodium hydroxide (2.4 gm., 0.6moles) in 3.0 ml of water was added. The mixture was warmed to 50° andstirred under nitrogen for 10 minutes to form the sodium thiophenatesalt. A solution of 2-chloro-5-(trifluoromethyl)pyridine (10.9 gm., 0.06moles) in 60 ml of dimethylsulfoxide was then added all at once. Themixture was heated to 100° and held there for 11/2 hours. At the end ofthis time it was poured into 500 ml of cold water. An emulsion formedtherefore 60 ml of a saturated solution of ammonium chloride was added.The product precipitated as a sticky solid. The aqueous layer wasdecanted, the solid washed with more water then taken up in hot heptane,dried with solid sodium sulfate and decolorized with Norite. In thefiltrate a white solid product precipitated and was separated and foundto have a melting temperature of 89°-93° C.

The so-prepared 4-((5-(trifluoromethyl)-2-pyridinyl)thio)phenol (10gms., 0.037 moles) was dissolved in 80 ml of dimethylsulfoxide and drypowdered sodium hydroxide (6.7 gm., 0.37 moles) was added. The mixturewas warmed to about 40° and stirred until the base was all in solutionindicating that the desired sodium phenate had formed. Ethylbromopropionate (6.7 gm., 0.37 moles) was then added all at once. Thereaction was run at 100°-105° for 2.0 hours, then cooled and poured into450 ml of cold water. The ester was extracted into methylene chloride,the extract dried and solvent removed leaving the product as an oilweighing 13.5 gm.

This was used without further purification for the next step which washydrolysis of the ester to the metal salt in aqueous alkaline medium.

The ethyl-2-(4-((5-trifluoromethyl)-2-pyridinyl)thio)phenoxy)propionate(13.5 gm., 0.37 moles) was dissolved in 50 ml of 95% ethanol and asolution of sodium hydroxide (3.0 gm., 0.075 moles) in 25 ml of waterwas added. The mixture was refluxed at 80° for about 6.0 minutes thencooled, poured into 400 ml of cold water and extracted with 250 ml ofmethylene chloride to remove any base insoluble impurities. The aqueoussolution containing the sodium salt of the acid was acidified to pH 1with concentrated hydrochloric acid. The product which precipitated as agummy solid was washed with water (after decanting) and taken up in hotmethylcyclohexane. On cooling the product precipitated as white crystalshaving a melting temperature of 118°-120° C. and a composition of, byweight, 52.38% carbon; 3.66% hydrogen; 4.00% nitrogen and 9.07% sulfur.The theoretical composition of2-(4-((5-trifluoromethyl)-2-pyridinyl)thio)phenoxy)propanoic acid is52.5% carbon; 3.5% hydrogen; 4.08% nitrogen and 9.34% sulfur.

EXAMPLE 13

4-Mercaptophenol (6.4 gm., 0.051 moles) was dissolved in 70 ml ofdimethylsulfoxide and a solution of sodium hydroxide (2.04 gm., 0.051moles) in a 3.0 ml of water was added. The mixture was warmed to about50° and stirred under nitrogen for 10 minutes to form the sodiumthiophenate salt. A solution of 2,3-dichloro-5-(trifluoromethyl)pyridine(11.0 gm., 0.051 moles) in 60 ml of dimethylsulfoxide was next added allat once. The mixture was then heated at 95°-100° for 2.5 hours. At theend of this time it was poured into 500 ml of cold water and allowed tostand for 45 minutes. The solid was then collected on a filter, washedand taken up in about one liter of boiling hexane. The productprecipitated on cooling as a white solid melting at 94°-96° C.

The so-prepared 4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)thio)phenol(11.0 gm., 0.036 moles) was dissolved in 80 ml of dimethylsulfoxide anddry powdered sodium hydroxide (1.44 gm., 0.036 moles) was added. Themixture was warmed and stirred until the base was all in solutionshowing that the desired sodium phenate had formed. Ethylbromopropionate (6.5 gm., 0.036 moles) was then added all at once. Thereaction was run at 100° for 2.0 hours then cooled and poured into 500ml of water. Most of the product precipitated as a white semi-solid. Theaqueous layer which was decanted off was extracted with 300 ml ofmethylene chloride. The extract was separated, solvent removed and theresidue added to the main product. This was washed thoroughly with waterto remove residual dimethylsulfoxide and used without furtherpurification for the hydrolysis step.

The so-preparedethyl-2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)thio)phenoxy)propionate(14.6 gm., 0.036 moles) was dissolved in 60 ml of 95% ethanol and asolution of sodium hydroxide (2.9 gm., 0.072 moles) in 25 ml of waterwas added. The mixture was heated at reflux for about 4 minutes, thencooled and poured into 400 ml of water. The solution was acidified to pH1 with concentrated hydrochloric acid which precipitated the product asa sticky solid. This was taken up in a boiling mixture of hexane andmethyl cyclohexane. After drying, filtering and cooling, the whitecrystalline product separated and was collected on a filter andexhibited a melting temperature of 132°-134° C. and was found tocontain, by weight, 47.64% carbon; 3.14% hydrogen; 3.51% nitrogen; 9.25%chlorine and 8.44% sulfur. The theoretical composition of2-(4-((3-chloro-5-trifluoromethyl)-2-pyridinyl)thiophenoxy)propanoicacid is 47.69% carbon; 2.93% hydrogen; 3.70% nitrogen; 9.38% chlorineand 8.48% sulfur.

EXAMPLE 14

Ninety ml of thionyl chloride were added to 9.0 g of2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoicacid and the mixture was refluxed for 34 minutes. The excess thionylchloride was removed on a still and the resulting acid chloride was putin solution in 30 ml of benzene. This was added to a reaction flaskcontaining 2.1 g methoxy amine hydrochloride in 20 ml of benzene plus asolution of 3.8 g of potassium carbonate in 31/2 ml of water. Thereaction mixture was then refluxed for 2 hours. The salt was filteredoff and the volatiles removed on the rotary evaporator. The crude solidswere taken up in heptane and crystallized. From this 6.75 g of whitesolid were obtained which had a melting point of 135°-6° C. and anelemental analysis of, by weight: C=48.98%; H=3.69%; N=7.16%; andCl=8.90%. The theoretical composition of2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)-N-methoxy-propanamideis C=49.18%; H=3.61%; N=7.17%; and Cl=9.07%.

EXAMPLE 15

Sixty ml of thionyl chloride were added to 6.0 g of2-(4-(3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoicacid and the mixture was refluxed for 30 minutes. The excess thionylchloride was removed on a still using aspirator vacuum. The resultingacid chloride was put in solution in 25 ml toluene. This solution wasthen added to a reaction flask containing 2.1 g butoxy ethanol (DOWANOLEB®), 1.85 g triethyl amine and 27 ml toluene and the mixture refluxedfor about 2 hours. The salt was filtered off and the volatiles removedon a rotary evaporator. The crude product was taken up in n-hexane,purified with norite activated carbon and the hexane removed on therotary evaporator. 7.05 g of amber oil were obtained which had arefractive index of 1.5061 at 25° C. and an elemental analysis of:C=54.27%; H=4.97%; N=3.21%; and Cl=7.77%. Calculated values for2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)-propanoicacid, 2 -butoxyethyl ester are: C=54.61%; H=5.02%; N=3.03%; andCl=7.68%.

EXAMPLE 16

Eighty ml of thionyl chloride were added to 8.0 g of2-(4-(3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoicacid and the mixture was refluxed for 38 minutes. The excess thionylchloride was then removed on a still using aspirator vacuum. Theresulting acid chloride was put into solution in 30 ml toluene. Thissolution was then added to a reaction flask containing 2.1 g of butylmercaptan, 2.5 g of triethyl amine and 25 ml of toluene. The mixture wasslowly heated to 98° C. over a one hour period and then taken to refluxand refluxed for about 45-50 minutes. The salt was filtered out and thevolatiles removed on a rotary evaporator. The crude product was taken upin n-hexane, purified with norite activated carbon and the hexaneremoved on the rotary evaporator. The resulting 9.1 g of amber oil and arefractive index of 1.5330 at 25° C. and an elemental analysis of:C=52.39%; H=4.46%; N=3.32%; Cl=8.08%; and S=7.1%. The theoreticalcomposition for2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoicacid-S-butyl ester is: C=52.59%; H=4.41%; N=3.23%; Cl=8.17%; andS=7.39%.

The compounds of the present invention have been found to be suitablefor use in methods for the pre and postemergent control of annual andperennial grassy weeds. The active ingredients of the present inventionhave been found to have advantage over prior art compounds in thecontrol of perennial grassy weeds in that the present compounds controla broader spectrum of such weeds than the counterpart compounds whileexhibiting a higher level of activity or control at like dosage rates.In addition, the present compounds are sufficiently tolerant towardsmost broad leafed crops to contemplate control of grassy weeds thereinat substantially commercially practicable levels, particularly so withthe preferred compounds.

For all such uses, unmodified active ingredients of the presentinvention can be employed. However, the present invention embraces theuse of a herbicidally-effective amount of the active ingredients incomposition form with an inert material known in the art as an adjuvantor carrier in solid or liquid form. Thus, for example, an activeingredient can be dispersed on a finely-divided solid and employedtherein as a dust. Also, the active ingredients, as liquid concentratesor solid compositions comprising one or more of the active ingredientscan be dispersed in water, typically with aid of a wetting agent, andthe resulting aqueous dispersion employed as a spray. In otherprocedures, the active ingredients can be employed as a constituent oforganic liquid compositions, oil-in-water and water-in-oil emulsions orwater dispersions, with or without the addition of wetting, dispersing,or emulsifying agents.

Suitable adjuvants of the foregoing type are well known to those skilledin the art. The methods of applying the solid or liquid herbicidalformulations similarly are well known to the skilled artisan.

As organic solvents used as extending agents there can be employed,e.g., benzene, toluene, xylene, kerosene, diesel fuel, fuel oil, andpetroleum naptha, ketones such as acetone, methylethyl ketone andcyclohexanone, chlorinated hydrocarbons such as carbon tetrachloride,chloroform, trichloroethylene, and perchloroethylene, esters such asethyl acetate, amyl acetate and butyl acetate, ethers, e.g., ethyleneglycol monomethyl ether and diethylene glycol monomethyl ether,alcohols, e.g., methanol, ethanol, isopropanol, amyl alcohol, ethyleneglycol, propylene glycol, butylcarbitol acetate and glycerine. Mixturesof water and organic solvents, either as emulsions or solutions, can beemployed.

The active ingredients can also be applied as aerosols, e.g., bydispersing them by means of a compressed gas such as one of thehydrocarbon successors to the fluorocarbons which are shortly to bebanned.

The active ingredients of the present invention can also be applied withsolid adjuvants or carriers such as talc, pyrophyllite, synthetic finesilica, attapulgus clay, kieselguhr, chalk, diatomaceous earth, lime,calcium carbonate, bentonite, Fuller's earth, cotton seed hulls, wheatflour, soybean flour, pumice, tripoli, wood flour, walnut shell flour,redwood flour and lignin.

As stated, it is frequently desirable to incorporate a surface-activeagent in the compositions of the present invention. Such surface-activeor wetting agents are advantageously employed in both the solid andliquid compositions. The surface-active agent can be anionic, cationicor nonionic in character.

Typical classes of surface-active agents include alkyl sulfonate salts,alkylaryl sulfonate salts, alkylaryl polyether alcohols, fatty acidesters of polyhydric alcohols and the alkylene oxide addition productsof such esters, and addition products of long-chain mercaptans andalkylene oxides. Typical examples of such surface-active agents includethe sodium alkylbenzene sulfonates having 10 to 18 carbon atoms in thealkyl group, alkyl phenol ethylene oxide condensation products, e.g.,p-isooctylphenol condensed with 10 ethylene oxide units, soaps, e.g.,sodium stearate and potassium oleate, sodium salt of propylnaphthalenesulfonic acid, di(2-ethylhexyl)ester of sodium sulfosuccinic acid,sodium lauryl sulfate, sodium decane sulfonate, sodium salt of thesulfonated monoglyceride of coconut fatty acids, sorbitan sesquioleate,lauryl trimethyl ammonium chloride, octadecyl trimethyl ammoniumchloride, polyethylene glycol glauryl ether, polyethylene glycol estersof fatty acids and rosin acids, e.g., Ethofat 7 and 13, sodiumN-methyl-N-oleyl taurate, Turkey Red Oil, sodium dibutylnaphthalenesulfonate, sodium lignin sulfonate, polyethylene glycol stearate, sodiumdodecyl benzene sulfonate, tertiary dodecyl polyethylene glycolthioether (nonionic 218), long-chain ethylene oxide-propylene oxidecondensation products, e.g., Pluronic 61 (molecular weight about 1000),polyethylene glycol ester of toll oil acids, sodiumoctophenoxyethoxyethyl sulfate, tris(polyoxyethylene)sorbitanmonostearate (Tween 60), and sodium dihexylsulfosuccinate.

The concentration of the active ingredients in solid or liquidcompositions generally is from about 0.003 to about 95 percent by weightor more. Concentrations from about 0.05 to about 50 percent by weightare often employed. In compositions to be employed as concentrates, theactive ingredient can be present in a concentration from about 5 toabout 98 weight percent. The active ingredient compositions can alsocontain other compatible additaments, for example, phytotoxicants, plantgrowth regulants, pesticides and the like and can be formulated withsolid particulate fertilizer carriers such as ammonium nitrate, urea andthe like.

The present compositions can be applied by the use of power dusters,boom and hand sprayers, spray dusters, by addition to irrigation water,and by other conventional means. The compositions can also be appliedfrom airplanes as a dust or a spray since the active ingredients areeffective at very low application rates.

The active ingredients of the present invention including methyl2-((4-(5-trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate;2-((4-(5-(trifluoromethyl)-3-chloro-2-pyridinyl)oxy)phenoxy)propionamide;2-((4-(5-trifluoromethyl)-2-pyridinyl)oxy)phenoxypropanoic acid andsalts thereof according to the present invention; butyl2-((4-(5-trifluoromethyl)-3-chloro-2-pyridinyl)oxy)phenoxypropanoate;2-((4-(5-trifluoromethyl)-2-pyridinyl)-oxy)phenoxy)propionamide N-methyl2-((4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanamide and2-(4-((3-chloro-5-trifluoromethyl-2-pyridinyl)thio)phenoxy propanoicacid have been found to possess desirable herbicidal activity in generalagainst grassy weeds such as foxtail, barnyard grass, wild oats andcrabgrass in preemergent operations and also against the same grassesand particularly seedling Johnson grass in postemergent operations.These compounds possess unique activity in being effective in thecontrol broadly of all or most of Johnson grass, quack grass, bermudagrass, orchard grass, Dallis grass and cogon grass, all perennial grassyweeds, while being tolerant to fairly tolerant to broadleaf crops suchas cotton and soybeans.

The active ingredients of the present invention including the compoundsjust above listed have been found to possess particularly desirableherbicidal activity against wild oats, foxtail, barnyard grass,crabgrass and seedling Johnson grass in postemergent operations, as wellas desirable broad spectrum activity against the perennial grassy weedslisted above and at lower dosage rates than the substituted propanoatesand propanols of the prior art while showing a greater tolerance tobroad leaf crops.

The present compounds which are substituted propanols or propyl ethersare more effective in preemergent operations than in postemergentapplications.

The exact rate to be applied is dependent not only on a specific activeingredient being applied, but also on a particular action desired (e.g.,general or selective control), the plant species to be modified and thestage of growth thereof as well as the part of the plant to be contactedwith the toxic active ingredient. Thus, it is to be understood that allof the active ingredients of the present invention and compositionscontaining the same may not be equally effective at similarconcentrations or against the same plant species. In non-selectivepreemergence and foliar treatments, the active ingredients of theinvention are usually applied at an approximate rate of from about 0.5to about 5 pounds/acre, but lower or higher rates may be appropriate insome cases such as 0.01 to about 20 pounds/acre or more. In preemergentoperations for selective uses a dosage of about 0.05 to about 20pounds/acre or more is generally applicable, a rate of 0.2 to 4pounds/acre being preferred and about 0.75 to about 1 pound/acre beingmost preferred.

In selective postemergent operations a dosage of about 0.01 to about 20pounds/acre or more is generally applicable, although not all compoundsare equally effective and some weeds are more difficult to control.Thus, a dosage rate in the range of about 0.05 to about 0.75 pounds/acreis preferred in postemergent control of annual grassy weeds, while about0.5 to about 5 pounds/acre is a preferred dosage range for thepostemergent control of perennial grassy weeds.

In view of the foregoing and following disclosures, one skilled in theart can readily determine the optimum rate to be applied in anyparticular case.

EXAMPLES 17-40

In representative operations, each compound to be utilized in a seriesof tests is dissolved in acetone to one half of the final volume (twicethe final concentration) to be used and the acetone solution in eachcase is admixed with an equal volume of water containing 0.1 percent byweight of Tween-20 surface active material (Tween 20 is a trademark ofAtlas Chemical Company). Each compound is selected from a groupconsisting of compounds according to the invention. The compositions,generally in the nature of an emulsion, were employed to treat separaterespective seed beds of sandy loam soil of good nutrient content whereineach seed bed contained separate groups of a known number of good viableseeds, each group being of one of a predetermined plant species. Thevarious beds were positions side by side and exposed to substantiallyidentical conditions of temperature and light. Each bed was maintainedso as to prevent any interaction with test compounds in different seedbeds. Each seed bed was treated with one of the compositions as a soildrench applied at one of two predetermined rates to deposit apredetermined amount of a given test compound uniformly throughout thesurface of the bed. The compositions were applied to the seed beds sothat different seed beds of a given plant species were treated with oneof each of the test compounds. Another seed bed was treated only withwater to serve as a control. After treatment, the seed beds weremaintained for two weeks under greenhouse conditions conducive for goodplant growth and watered as necessary. The specific plant species, testcompound and dosage and the percent preemergent control obtained are setforth in the table below. Control refers to the reduction in growthcompared to the observed results of the same species.

    __________________________________________________________________________    PREEMERGENCE CONTROL OF PLANT SPECIES                                          ##STR21##                                                                                               Plant Species                                                                                 Barn-                              Compound Tested     Dosage In        Wild                                                                             Fox-                                                                             yard                                                                              Crab-                                                                             Johnson                    X  Y  Z           T Lbs Per Acre                                                                         Corn                                                                             Rice                                                                             Wheat                                                                             Oats                                                                             tail                                                                             Grass                                                                             grass                                                                             Grass                      __________________________________________________________________________    Cl CF.sub.3                                                                         CN          O 1       95                                                                               70                                                                               0   40                                                                              100                                                                               95 100 100                                            .25     40                                                                               0  0   0  95                                                                               0   40  70                        CF.sub.3                                                                         --                                                                                ##STR22##  O 0.5 0.125 0.063                                                                      100 100  60                                                                      100  80  0                                                                       100 100   20                                                                      100 100 100                                                                      100  95  90                                                                      100 100 100  90                                                                       100 100  98                Cl CF.sub.3                                                                          ##STR23##  O 1 0.25 100  60                                                                           90  20                                                                          100 100  80                                                                          100  80                                                                          100 100 100                                                                           100  80                    CF.sub.3                                                                         Cl                                                                                ##STR24##  O 0.5 .125                                                                             100  80                                                                           98  0                                                                           100  70  0                                                                           100  90                                                                          100 100 100                                                                           100  80                    CF.sub.3                                                                         --                                                                                ##STR25##  O 0.5 .125                                                                             100  95                                                                          100  60                                                                          100 100  60                                                                          100  98                                                                          100 100                                                                           100 100                                                                           100  95                    CF.sub.3                                                                         CF.sub.3                                                                         CN          O 10     -- -- --   40                                                                               95                                                                              100 100 --                         CF.sub.3                                                                         --                                                                                ##STR26##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR27##  S 0.125 .063                                                                           100  98                                                                          100 100                                                                           30  95  50                                                                           95  90                                                                          100 100                                                                           100 100                                                                            97  97                    Cl CF.sub.3                                                                          ##STR28##  O 1 .25  100  60                                                                           98  0                                                                            40 --                                                                             90  40                                                                          100  60                                                                          100 100                                                                           100  90  90                    CF.sub.3                                                                         CF.sub.3                                                                          ##STR29##  O 1 .25   70  0                                                                            0 --                                                                             60  90  70                                                                           80  80                                                                           60 100  90  60                    CF.sub.3                                                                         --                                                                                ##STR30##  O 1 .25   70  0                                                                            95  20                                                                           98  90  0                                                                           100  80                                                                           60 100  90  60                    CF.sub.3                                                                         -- CN          O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl CN          O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         CF.sub.3                                                                          ##STR31##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         CF.sub.3                                                                         CH.sub.2 OH O 10     -- -- --   90                                                                               98                                                                               98  95 --                         CF.sub.3                                                                         Cl CH.sub.2 OH O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR32##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR33##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         CF.sub.3                                                                          ##STR34##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR35##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR36##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         Cl CF.sub.3                                                                          ##STR37##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         CF.sub.3                                                                          ##STR38##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         Cl                                                                                ##STR39##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         CF.sub.3                                                                         --                                                                                ##STR40##  O 10     -- -- --  100                                                                              100                                                                              100 100 --                         __________________________________________________________________________

EXAMPLES 42-65

So as to illustrate clearly the phytotoxic properties of the variousactive ingredients of the present invention applied postemergently, agroup of controlled greenhouse experiments is described below.

Various species of plants were planted in beds of good agricultural soilin a greenhouse. After the plants had emerged and grown to a height ofabout 2-6 inches a portion of the plants were sprayed with an aqueousmixture, made by mixing a selected active ingredient and emulsifier ordispersant with about 1:1 water-acetone, employing sufficient amounts ofthe treating composition to provide application rates of 4000 parts permillion (ppm) or about 10 pounds per acre and in some cases at lowerrates. Other portions of the plants were left untreated to serve ascontrols.

After a period of 2 weeks, the effect of the respective test ingredientsused on respective groups of plants was evaluated by a comparison withthe control groups of the plants. The results are tabulated in thefollowing table.

    __________________________________________________________________________    POSTEMERGENCE CONTROL OF PLANT SPECIES                                         ##STR41##                                                                                             Plant Species                                                                                 Barn-                                Compound Tested                    Wild                                                                             Fox-                                                                             yard                                                                              Crab-                                                                             Johnson                      X  Y  Z        T Dosage in PPM                                                                         Corn                                                                             Rice                                                                             Wheat                                                                             Oats                                                                             tail                                                                             Grass                                                                             grass                                                                             Grass                        __________________________________________________________________________    Cl CF.sub.3                                                                          ##STR42##                                                                             O 500 125 100  80                                                                           0 --                                                                            40  0                                                                             100  80                                                                          100  98                                                                          100 100                                                                           100 100  98                      CF.sub.3                                                                         Cl                                                                                ##STR43##                                                                             O 125 31.5                                                                               95  70                                                                          98 90                                                                            40 20                                                                              70  70                                                                          100  98                                                                           80 100 100                                                                           100 100                      CF.sub.3                                                                         Cl                                                                                ##STR44##                                                                             O 62.5 15.6                                                                             100 100                                                                          80 80                                                                            60 60                                                                              80  98                                                                          100  98                                                                          100 100                                                                           100 100 100                      CF.sub.3                                                                         Cl                                                                                ##STR45##                                                                             O 62.5 15.6                                                                             100 100                                                                          90 30                                                                            95 60                                                                             100 --                                                                           100  95                                                                          100 100                                                                           100 100 100                      CF.sub.3                                                                         --                                                                                ##STR46##                                                                             O 62.5 15.6                                                                              95  95                                                                          -- --                                                                            60 40                                                                             100  20                                                                          100  60                                                                           90 100 100  98                      CF.sub.3                                                                         --                                                                                ##STR47##                                                                             O 62.5 15.6                                                                             100  80                                                                          70 40                                                                            50 30                                                                              80  10                                                                           90  90                                                                           70  98 100  95                      Cl CF.sub.3                                                                          ##STR48##                                                                             O 500      60                                                                               0  0   0  0  0   60 100                          CF.sub.3                                                                         Cl                                                                                ##STR49##                                                                             O 62.5 15.6                                                                              80  60                                                                          99 60                                                                            90 80                                                                              98  90                                                                           90  90                                                                           90  98 100 100                      CF.sub.3                                                                         CF.sub.3                                                                         CN       O 4000    -- -- --  100                                                                               90                                                                              100 100 --                           Cl CF.sub.3                                                                         CN       O 4000    -- -- --  --  80                                                                               60 100 --                           Cl CF.sub.3                                                                          ##STR50##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         --                                                                                ##STR51##                                                                             O 4000    -- -- --  -- 100                                                                              100 100 --                           CF.sub.3                                                                         -- CN       O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl CN       O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         CF.sub.3                                                                          ##STR52##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         CF.sub.3                                                                         CH.sub.2 OH                                                                            O 4000    -- -- --   95                                                                               95                                                                               70  98 --                           CF.sub.3                                                                         Cl CH.sub.2 OH                                                                            O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl                                                                                ##STR53##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl                                                                                ##STR54##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         CF.sub.3                                                                          ##STR55##                                                                             O 4000    -- -- --   99                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl                                                                                ##STR56##                                                                             O 4000    -- -- --  100                                                                               98                                                                              100 100 --                           Cl CF.sub.3                                                                          ##STR57##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl                                                                                ##STR58##                                                                             O 4000    -- -- --  100                                                                              100                                                                              100 100 --                           CF.sub.3                                                                         Cl                                                                                ##STR59##                                                                             S  28  14 100  30  0                                                                       20 *-- -- --                                                                          60  0 --                                                                        100 100   80                                                                     100 100 100 100 100                  __________________________________________________________________________     *Wheat was not run at these lower dosage rates as control at 111 ppm was      only 20% and at 55.5 ppm control was zero.                                    Approximate pounds per acre application equivalent to ppm dosage rates ar     as follows: 111 ppm = 0.2 lbs/A; 55.5 ppm = 0.1 lb; 28 ppm = 0.05 lb; 14      ppm = 0.025 lb; 7 ppm = 0.013 lb/A.                                      

EXAMPLES 66-77

In a series of tests clearly demonstrating the herbicidal properties ofthe compounds of the present invention applied postemergently, variousmetal and amine salts of propanoic acids prepared in aqueous solution asdescribed hereinabove and brought initially to a dilution of 4,000 ppmwere applied to growing plants under greenhouse conditions.

Various species of plants were planted in a series of pots containinggood agricultural soil in a greenhouse. After some of the plants hademerged and grown to a height of about 2-6 inches some of the plantswere sprayed, respectively, with a respective one of the said aqueoussolutions, then diluted and sprayed on other respective selected plantsat lower rates, each species of plant not being run at all rates. Otherplants were left untreated to serve as controls. Still other plants,plants of Bermuda grass, blue grass, Johnson grass and cheat grass, wereallowed to grow to 6-8 inches then four times cut back to 2 inches andallowed to regrow, all over about a 6-7 week period providingestablished plants.

After a period of about two weeks, the effect of the respective testingredients used on various respective plants was evaluated bycomparison with the control group of plants. The results showed that thepotassium and triethylamine salts of2-((4-(5-trifluoromethyl)-3-chloro-2-pyridinyl)oxy)phenoxy)propanoicacid applied (a) at a rate of 4,000 ppm gave complete control of Bermudagrass, sorghum and barnyard grass while showing little or no control ofcotton; (b) at a rate of 2,000 ppm gave substantial to complete controlof bluegrass and rice while showing no effect on soybeans; (c) at a rateof 1,000 ppm gave complete control of Johnson grass, crabgrass andyellow foxtail; and (d) at a rate of 500 ppm exhibited complete controlof cheat grass, corn, wheat and wild oats.

In addition, the ethanolamine and sodium salts of2-4((-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acidapplied (a) at a rate of 4,000 ppm gave complete control of Bermudagrass, sorghum and barnyard grass while showing no adverse effects oncotton; (b) at a rate of 2,000 ppm gave 70% control of bluegrass andcomplete control of rice while having no adverse effects on soybeans;(c) at a rate of 1,000 ppm showed complete control of Johnson grass andcrab grass and fair to excellent control of yellow foxtail; and (d) at arate of 500 ppm gave complete control of cheat grass, corn, wheat andwild oats.

Further the ethylamine salt of2-((4-(5-chloro-3-trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoicacid and the ammonium salt of2-((4-(3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acidgave nearly as good control of the same plants at the rates recitedabove as described for the salts rated in the preceding paragraphs.

The same salts applied in preemergent operations using the solutionsdescribed above as well as in Examples 6 and 7 and applied at rates inthe range of about 10 to about 1.25 pounds per acre in a manner similarto that described for Examples 17-41 showed substantially complete tocomplete control of crabgrass, yellow foxtail, barnyard grass, wild oatsand wheat and no control of cotton velvet leaf or annual morning gloryat the higher rates and the same or substantially the same excellentcontrol at the lower rates.

EXAMPLES 78-79

In preemergent operations carried out in a manner similar to thatdescribed in Examples 17-41, using 10 pounds-acre of active ingredient,N,N-di-n-butyl 2-((4-(3,5-bis(trifluoromethyl)-2-pyridinyl)oxy)phenoxypropanamide gave 60 percent control of crabgrass, but no control of wildoats, foxtail, barnyard grass, cotton, pigweed, annual morning glory orvelvet leaf, while N,N-dimethyl2-((4-(5-trifluoromethyl-2-pyridinyl)oxy)phenoxy)propanamide showedcomplete control of wild oats, foxtail, barnyard grass and crabgrass.

In postemergent operations carried out in the same manner as thatdescribed in Examples 42-65, applying active ingredient at the rate of4,000 ppm, the above described N,N-di-n-butyl propanamide showed 80percent control of cotton and 60 percent control of velvet leaf but nocontrol of wild oats, foxtail, barnyard grass, crabgrass or annualmorning glory, while the above identified N,N-dimethyl propanamideexhibited complete control of wild oats, foxtail, barnyard grass andcrabgrass.

What is claimed is:
 1. A compound of the formula: ##STR60## wherein: Tis oxygen or sulfur;X is Cl, Br or CF₃ ; Y is H, Cl, Br or CF₃, providedat least one of X and Y is CF₃ ; Z is --CH₂ OR₅ or ##STR61## R₅ is H;and R₆ is C₁ -C₇ alkyl.
 2. The compound as in claim 1 wherein T isoxygen and Z is --CH₂ OR₅.
 3. The compound as in claim 1 wherein T isoxygen and Z is ##STR62##
 4. The compound as in claim 1 wherein X isCF₃, Y is H or Cl and T is oxygen.
 5. A composition comprising an inertcarrier and a herbicidally effective amount of a compound of theformula: ##STR63## wherein: T is oxygen or sulfur;X is Cl, Br or CF₃ ; Yis H, Cl, Br or CF₃, provided at least one of X an Y is CF₃ ; Z is --CH₂OR₅ or ##STR64## R₅ is H; and R₆ is C₁ -C₇ alkyl.
 6. The composition asin claim 5 wherein T is oxygen and Z is --CH₂ OR₅.
 7. The composition asin claim 5 wherein T is oxygen and Z is ##STR65##
 8. The composition asin claim 5 wherein X is CF₃, Y is H or Cl and T is oxygen.
 9. The methodof controlling undesired plant growth which comprises applying to thelocus of said plants a herbicidally effective amount of a compound ofthe formula ##STR66## wherein: T is oxygen or sulfur;X is Cl, Br or CF₃; Y is H, Cl, Br or CF₃, provided at least one of X and Y is CF₃ ; Z is--CH₂ OR₅ or ##STR67## R₅ is H; and R₆ is C₁ -C₇ alkyl.
 10. The methodas in claim 9 wherein T is oxygen and Z is --CH₂ OR₅.
 11. The method asin claim 9 wherein T is oxygen and Z is ##STR68##
 12. The method as inclaim 9 wherein X is CF₃, Y is H or Cl and T is oxygen.